Navegando por Palavras-chave "nanostructures"

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    Avaliação histomorfométrica e imunoistoquímica do uso da hidroxiapatia manométrica em defeitos ósseos na calota craniana de ratos
    (Universidade Federal de São Paulo (UNIFESP), 2016-06-29) Faria, Marcio Antonio [UNIFESP]; Simoes, Manuel de Jesus Simoes [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Currently it is considered a challenge to surgical reconstruction of bone defects created by trauma and degenerative diseases. It is eventually necessary to use autogenous bone or other bone substitute biomaterials, performing procedures grafts and transplants. As part of these biomaterials, contains the hydroxyapatites (HA), which have shown promising for behaving biocompatible way. However, it is known that the size of the HA particles is important in bone healing process, once the biomaterial should be reabsorbed to make room for the bone tissue. In this context, the hydroxyapatite nanometer (nHA) has a promising role in the healing process of the bone tissue because of their small size and approach the size of the natural HA of bone crystals. The objective of this study was to evaluate the effect of nHA paste (ReproBone ®) in bone defects created in the skull of Wistar rats after 7, 14 and 21 days, by histomorphometric and immunohistochemical analysis for VEGFA. The nHA was implanted in calvarial defects in the test group while the control group defects were filled only with blood clot. The animals were divided into 6 groups: GI (ctrl 7 days), GII (ctrl 14 days), GIII (ctrl 21 days), GIV (test 7 days), GV (trial 14 days), GVI (test 21 days). After surgery, the animals were euthanized and the calvaria removed for histological and immunohistochemical processing. The results showed that the test groups increased formation of bone tissue compared to control groups at 21 days was the total closure of the bone defect in the test group. There was a greater reactivity to Vegf in connective tissue region and the periphery of the newly formed bone in the test groups compared to control groups. It follows from the data obtained that nHA accelerates bone regeneration process at all times 7, 14 and 21 days and that its use could promote full healing of a critical defect in bone tissue.
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    Optical characterization of europium-doped indium hydroxide nanocubes obtained by Microwave-Assisted Hydrothermal method
    (ABM, ABC, ABPol, 2014-08-01) Motta, Fabiana Villela da; Marques, Ana Paula de Azevedo [UNIFESP]; Araújo, Vinícius Dantas de; Tavares, Mara Tatiane de Souza; Delmonte, Mauricio Roberto Bomio; Paskocimas, Carlos Alberto; Li, Máximo Siu; Nascimento, Rubens Maribondo do; Longo, Elson; Universidade Federal do Rio Grande do Norte Centro de Tecnologia Departamento de Engenharia de Materiais; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Universidade Estadual Paulista (UNESP)
    Crystalline europium-doped indium hydroxide (In(OH)3:Eu) nanostructures were prepared by rapid and efficient Microwave-Assisted Hydrothermal (MAH) method. Nanostructures were obtained at low temperature. FE-SEM images confirm that these samples are composed of 3D nanostructures. XRD, optical diffuse reflectance and photoluminescence (PL) measurements were used to characterize the products. Emission spectra of europium-doped indium hydroxide (IH:xEu) samples under excitation (350.7 nm) presented broad band emission regarding the indium hydroxide (IH) matrix and 5D0 → 7F0, 5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3 and 5D0 → 7F4 europium transitions at 582, 596, 618, 653 and 701 nm, respectively. Relative intensities of Eu3+ emissions increased as the concentration of this ion increased from 0, 1, 2, 4 and 8 mol %, of Eu3+, but the luminescence is drastically quenched for the IH matrix.